Photo Answers
Your tricky questions answered and key techniques revealed
When I take a shot of a reflection, it comes out darker than the subject – but not in some other images I see. Why is this? Keith Hooper
You are right to say that the reflection is darker than the
subject itself. This is because the reflected light coming off the subject and the light coming off the reflection in the water are not equal.
In the case of the water, some of the light hitting it continues into the water itself, so the intensity of the reflected light is obviously less.
How much less is dependent on several factors, such as the angle and strength of the light, so it’s impossible to say how much darker in terms of stops the reflection is likely to be. In my experience, it can vary from as little as two-thirds of a stop to as much as one-and-a-half-stops.
In terms of exposure, this gives you an imbalance to take into account. You can use a physical filter, such as a graduated neutral-density filter to help; that’s exactly what I did with this lily image. A one-stop ND grad over the brighter flower has helped to balance the exposure difference, but notice that the reflection is still slightly darker than the actual lily. In the images you’ve seen online, I’d guess the photographers have chosen to bring the reflection brightness up to match the subject itself.
That’s not difficult to do but, to my eye, it always looks slightly wrong if the reflection brightness is equal to the thing being reflected. If you want to keep things as natural as possible, try to have some differentiation between the two parts of the image. However, that’s very much a creative choice, and up to the individual to decide how they want to interpret the scene they are shooting.